摘要 |
<p>A variable flow resistance system can include a vortex device, with resistance to flow of a fluid composition through the vortex device being dependent on a rotation of the fluid composition at an inlet to the vortex device. Another system can include a second vortex device which receives a fluid composition from an outlet of a first vortex device, a resistance to flow of the fluid composition through the second vortex device being dependent on a rotation of the fluid composition at the outlet. Another system can include a first vortex device which causes increased rotation of a fluid composition at an outlet thereof in response to an increase the fluid composition velocity, and a second vortex device which receives the fluid composition from the outlet, a flow resistance through the second vortex device being dependent on the rotation of the fluid composition at the outlet.</p> |